To understand how albumin production by liver parenchymal cells is inhibited directly by ethanol, we are characterizing this specialized function during the growth cycle of proliferation competent adult rat hepatocytes in primary "monolayer" culture. Ethanol's actions will be examined at varying doses after acute and chronic exposure. The dependence of albumin secretion, synthesis and "turnover" on (a) cell density, (b) growth state, (c) growth rate, and (d) nutritional conditions will be explored. Albumin will be measured by specific radioimmunoassay, immunoprecipitation and slab gel electrophoretic procedures. Cell growth will be measured quantitatively and qualitatively as described in Leffert et al. (PNAS 71:1834-1838, 1978) and Koch and Leffert (Cell 18:153-163, 1979). The total numbers of albumin mRNA-like sequences during the growth cycle also will be measured by nucleic acid hybridization of cellular RNA to specific albumin 32p-labelled cDNA probes. Since the cultures show a growth-state dependent change in pyrazole-sensitive alcohol dehydrogenase activity, we will see if ethanol metabolism is required for its function-inhibiting effects.